Wuice (also spelled Wüs) is a non-alcoholic drink composed of any type of juice and water. The type of juice and ratio of these components is up the to drinker. It is most commonly made using orange juice (many drinkers show a brand bias for Tropicana, although there is no established research to show any advantage over other brands) and water in an approximately 50/50 ratio. Although the drink wuice dates back to antiquity (it was known as "diluted juice"), the current formal name is relatively new, and its origins are unknown. One common myth about wuice is that it has four times the amount of Vitamin C and half the calories of normal juice, however, this has yet to be proved through any sort of comprehensive scientific study.

As wuice has gradually evolved, variations in practice have appeared across the wuice-drinking community . Most notable among these are two developments, the rise in popularity of "harsh wuice" (defined as wuice containing significantly more than 50 percent water) and wuice tea (wuice made with water of a temperature at or around 100 degrees Centigrade). The smoother, sweeter taste and texture of wuice tea combined with the perception (right or wrong) that it contains 8 times the amoung of Vitamin C of normal juice (the high temperature having unlocked even more Vitamin potential through increased molecular motion) has made wuice tea a popular gateway beverage to the harsher wuice varieties.

Wuice serves many practical functions. It is a highly economical beverage as a given volume of juice creates more than twice that volume of wuice while still allowing for maximum taste.